docs: def iso_date(d) -> str:
          """
          Return iso format of a date
  
          Args:
              d:
          Returns: str
  
          """
          if isinstance(d, datetime):
              return d.isoformat()
          elif isinstance(d, date):
              return datetime.combine(d, datetime.min.time()).isoformat()
          else:
              try:
                  datetime.strptime(d, '%Y-%m-%dT%H:%M:%S')
                  return d
              except ValueError:
                  try:
                      datetime.strptime(d, '%Y-%m-%d')
                      return d + "T00:00:00"
                  except ValueError:
                      pass
          raise ISODateError("Can not convert value to ISO format for kg")